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OlDatZMan

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About OlDatZMan

  • Rank
    Newbie

Profile Information

  • Gender
    Male
  • Location
    WA on island near water
  • Cars
    720 4x4, Metros, Leaf, GMC, VWs, the rest exceeds available space
  • Interests
    Too many
  • Occupation
    Half retired, sheet metal recently

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  1. OlDatZMan

    Boink boink

    No answer yet to my question so I'll rephrase: Shouldn't I be able to clearly sense compression on each cylinder when turning over the crank on this Z24 using a 1/2 ratchet even if the ratchet action isn't very fast? I know I certainly can feel compression when hand cranking my 51 Farmall Super A and it's only a 113CID 4 cylinder with 6:1 compression. I'll try just turning the crank pulley by hand which will make it easier to feel resistance. Just answered my own question: I can't turn the engine over by hand gripping the crank pulley. So I guess it does have compression and it's time to assemble a few more things to do a starter spin. Also knit together the exhaust system back together.
  2. OlDatZMan

    Boink boink

    That's the mistake I made last week. I left out some things this post; didn't want it to be too long. Rockers but 4 only the #1 valve lash is set. ******* Edit/add: I can't say that I have zero compression. I'm turning it over with a 1/2" ratchet on the crank which admittedly is not fast, but there doesn't seem to be much resistance, even thinking about a 5hp mower motor. I set the valves on the other 3 cylinders just now so all 4 should be talking to me especially since before all this recent work I had over 170 on a compression test (6 revolutions using the starter) on 1, 2, and 4. I haven't spun it with the starter yet but I guess that's the next try, but wanted to get some good news before I started reassembling all the things that came off changing the head gasket. Intake manifold is on but not exhaust. Cam sprocket bolt is snug but not torqued in case I needed to pull it again to change the valve timing which doesn't seem likely now.
  3. OlDatZMan

    Boink boink

    7-11-18, last three days: EZ LOK threaded insert installed to repair pulled threads on the intake side at the center rocker mount boss with the oil port. Head back on with new gasket and cam sprocket back on. Crank turns easily, no obstructions. @ crank mark TDC, #1 and #4 pistons at TDC line on cam boss just to right of rocker post casting line #1 valve lobes at 4:00 & 8:00 distributor rotor at ~ 7:00 from driver’s fender, ie pointing to #1 intake plug distributor wire No compression on #1 either with finger in the hole or spark plug snugged--haven't checked other cylinders and don't see the need to if #1 doesn't work. Crank pulley and distributor have not been removed since it last ran, reasonably well with one cylinder at 118 for compression If I r otate the crank to where distributor rotor is pointed at 9 and 4 the crank pulley, crank TDC mark is about 45 degrees BTDC I don’t see how the chain could have jumped at all, certainly not 45 degrees. Chain is US made, probably replaced (before I got the truck) when the last head gasket went on and the head was milled flat, I think less than 40k mile ago. Distributor timing is a different issue than cam timing and compression. Distributor could have been previously pulled and put back in wrong but I should still have compression turning the crank, and the truck DID run reasonably well before I pulled the head. I've marked out the valve durations on a paper degree wheel and turned the crank while referencing the wheel and all seems correct. How can I not have compression?
  4. OlDatZMan

    Boink boink

    Forum slow today. Condolences to admins trying to troubleshoot. This reply didn't take, trying again: RE using a longer bolt to reach remaining good threads in head: Hole depth in head: 1 3/8" (maybe not threaded to the bottom) Minus 1.4" locate bush stickout = 1 1/8" max hole depth Bolt length: 3" from cap face Upper cam bearing block height to cap screw surface: 2.250" 3" - 2.250 = 3/4" bolt threads max available, also meaning all hole threads at max bolt depth are failed 1 3/8 hole depth + 2.250 upper cam block = 3 5/8" max depth for new bolt (if hole threaded to bottom) 1 1/8" max hole depth - 3/4" OEM bolt engagement = 3/8" untouched threads at bottom of hole if the hole was threaded all the way to the bottom IF hole threaded all the way to the bottom, 3/8" might be enough for steel threads, but I don't think aluminum. And I doubt the hole is threaded to the bottom. Doesn't look very promising.
  5. OlDatZMan

    Boink boink

    I haven't measured the hole depth yet (I will now) but know the bolt went into the threads quite a ways, 6 or 8 turns. The OEM bolt is also long, 3". Finding a longer one would be harder than going to the local hardware store. Keeping the alignment bush means a new bush with an ID larger than the insert OD, meaning an even bigger hole and less material remaining for the insert. Also means finding a bigger bush and drilling the lower cam bearing block to match. One might possibly find a bush about the dia of the insert, chamfer the inside of one end, slice it down to a ring maybe 1/16" tall, chamfer the outside bottom of the OEM locate bush, and cut down its length so the internal and external chamfers f the two bush's engaged like a compression fitting. That's a lot of ifs, and grinding down a bush into a ring doesn't sound safe or fun. I don't have a reasonable solution yet. Just about anything is repairable, but there comes a time when someone not consumed by the repair just says "get another head'. Not there yet but the thought is closer than it used to be.
  6. OlDatZMan

    Charles Yeager

    I probably read Yeager's book 10 times. It's a great read about someone who could fly the pants off of anything he got into. Yes, he wouldn't quit, but he also had a number of traits including great eyesight, a feel for the air and the plane, and an unusual ability to grok mechanical systems that others didn't have. But I quit re-reading him when he ridiculed the Voyager flight. Dick Rutan probably was not Yeager class, but the Voyager book's description of the Voyager's flying qualities combined with the days involved and weather made that a huge achievement. The best other flying books I know are Saburo Sakai's (Martin Caidin) book Samurai, and the copter book Chicken Hawk by Robert Mason. I met Sakai once, at a fly-in in eastern WA. Watchign the long line of people in the hand-shaking line, I don't think many if any knew who Sakai was. That said, all air combat books need to be gauged relative to The Blond Knight of Germany, about Eric Hartmann.
  7. OlDatZMan

    Anti-seize ins and outs--general info

    Followup from Chesterton: "When calculating torque or referencing torque values from a chart it’s not uncommon that the default value being used of a dry nut factor is .2. This value .2 is based on using new clean hardware bolts/studs & nuts. The 725 Anti-Seize uses a .18 k factor for the dry nut factor. You can either re-calculated the torque value using the .18 factor or just reduce the torque value by 10%. The best benefit about using anti-seizes with lower k nut factors that it helps you achieve the required load at a lower torque. Which in turn speeds up/shortens the installation time of the application. " Another benefit is adding some lubrication other than oil to reduce stiction. I want bolts to stay in and tight, but l also want multiple torqued bolts on a single assembly to have equal torque, and varying stiction can cause a wider variation of torques. Using a smidge of AS on my rocker bolt threads and under the cap head might have prevented the pulled out threads I'm dealing with now. Nice to know about iodine but I can't think of a bolt I'd never want to remove.
  8. OlDatZMan

    Boink boink

    Thanks Charlie and Crash. For the present I'm pushing on to see whether I'm headed for a reasonable repair time and cost, or down a rabbit hole. It's nice to see there are more choices than Heli. For any insert option I would need to remove the rocker bolt hole cam bearing locate bushing which would delete the locating benefit Nissan thought it needed. Is that acceptable? I don't see an easy or even reasonable way to install an insert and retain the locate bush. There's not much room on the top of the cam block mount tower. Drilling out for a threaded insert reduces the material needed to anchor an insert. Concern about insert purchase took me here (a Helicoil pdf): https://media.boellhoff.com/files/pdf1/helicoil-tangfree-en-0150.pdf There the relevant term is "residual wall thickness", the amount of material remaining after the original bolt bore is drilled out to the spec'd insert OD, found on pages 13, 17, and 18. For Heli: residual wall thickness = 0.375 x OD of insert M8-1.25 Helicoil OD is 9.62mm or 0.3787” Residual wall thickness for M8 Heli is 0.375 x 0.3787 = 0.142” 0.142” x 2 (walls) = 0.284” Total residual wall thickness of 0.284” plus M8 Heli OD of 0.3787” = 0.407" The locate bush is not centered on the cam block mount tower. My measured distance between aft oil feed bore and fwd cam block tower edge is 0.626”, which is sufficient. My measured minimum distance is between the locate bush OD and cam mount tower is 0.090” Therefore the residual wall thickness (at least for Helicoil) is less than stated minimum in the bore arc closest to the cam. I'd prefer EZ Lok for cost and simplicity but EZ LOK’s web site is a hassle--lots of scrolling and numerous pages without finding a residual wall thickness for their insert. EZ could learn something from the pdf above. But there is a distributor about 10 miles from me. This repair would be much be less time and hassle if done with the head on the block where it is now, rather than pulling off the head and then supporting it precisely on a 10" dia drill press table. What are your opinions about drilling with a hand drill with head installed vs pulling the head off and eating the time for that and another head gasket to drill out for the insert? The bolt is long so the drill angle would have to be fairly exact.
  9. OlDatZMan

    Boink boink

    >(the half moon) It's got to be soft enough to crush in order to seal as a valve cover gasket. The new one I put in was a tad taller and hard enough and resisted crushing enough that I had a small oil leak around it and wished I had put back in the old one rather than a new one. That is, before I dropped it down the hole. >Well is the cam timed properly? TDC should see both valves on #1 closed. Are they? Cam only has to be off about two teeth 18 degrees to have a valve not closed at TDC. Yes it was heartening that both #1 valves were closed at TDC, and timing was off/advanced just 1 tooth from my estimate when the crank was at BDC. Easy change to make when I took off the rockers again to flip them over, and by then I was ready for all this to be over.......... Except the 2nd from aft pass side rocker bolt pulled out the alum head's threads, not even on the final torquing round, at less than Nissan's torque number. So as I wrote someone recently, things are never so bad they can't get worse. First thought after I got done swearing was Helicoil, which I've never used, but those and its competitors Pioneer and Time-Sert are around $100 for the insert and very special insert tool and left hand tap. And a GM repair site talking about rocker bolt thread repair said they had had too many Helicoils fail and have gone to Time-Sert which isn't the coil spring kind of thing a Heli Coil is, instead it's an internally and externally threaded bushing. Looking farther, E-Z LOK is the latter type and cheap because you don't need special tools, only the insert. So does anyone have direct experience with several of these thread fix brands especially E-Z Lok?.....and if so, would you pull the head off to be able to put it on a drill press for drilling oversize, or would you leave the head on and use a hand drill. I am sounding more placid than I am. Links I found: (I'm guessing and not certain that the bolt in question is an M12-1.77, that's just what I looked for) Time-Sert https://www.mechanicstoolsandbits.com/time-sert/metric-kits/metric-kits- E_Z LOK https://www.amazon.com/Z-Externally-Threaded-Stainless-M12-1-75/dp/B002KLT1RU/ref=sr_1_6?ie=UTF8&qid=1530753979&sr=8-6&keywords=e-z+lok+threaded+insert+m12 Pioneer (no details) http://www.pioneerfasteners.com/ct20510/thread-repair-inserts
  10. OlDatZMan

    Boink boink

    I'm making this post out of a sense of reporting duty, with the risk it may harm my pristine integrity........... I had mused on the possible "urethane" composition of the little half moon, and having put in urethane suspension bushings I knew that urethane is oft chosen because of its resistance to pressure and fragmenting. Using a hammer or other blunt instrument to break up a chunk of rubber or urethane questions the choice of tool. Never the less having flipped the rockers over yesterday to allow the crank and cam to rotate while preventing any cam valve movement, I went out this AM to have a showdown with the hidden impediment and grind it up with resolve using my longest 1/2 breaker bar to overcome any resistance. There was none. Over it went, smooth as silk, over and over with nary a hint of pause. It was a gigantic letdown combined with shock. So I did the next step, stuck my finger in #1 spark hole, and turned it again. No compression. No compression on #2, 3 or 4 either. This is not fair. With new valves sprung closed and pistons going up and down this is impossible. I had begun to wonder if the shop gremlins has switched their usual game of hiding my tools to a cooperative gang-up on my truck, but this kind of impossibility seems more like a wrinkle in the time space continuum. Possible causes: 1) 4 bent valves, very unlikely; 2) bad head gasket installation, very unlikely; 3) alien intervention, increasingly likely; 4) I'm departing sanity. The only rational response to this is a maniacal cackle echoing through the woods. I think there was one of those. ************************** 3:19: Three hours and a beach walk later: There is a #5: Extreme mental density. You probably figured it out already. All razzing accepted with humility.
  11. OlDatZMan

    Boink boink

    Honestly Charlie this was a cheap truck that has 200k miles, unknown maintenance, and has been popped slightly in the driver's side so the door doesn't close as it should. I got it for my son but I don't think he wants it. Above all, it is much more complex to work on than a 2wd truck which is the opposite of what I want. I like 4wd but they can't walk on water. Best thing about this is having the low side of the transfer case so you can go really slow. I have a lot of miles including 18 wheelers and autocross (not with a semi:-) and can drive most places in 2wd that most people think they need 4wd to get to. Falling into a ditch when it's slippery is one thing, but I'd bet that more than half of all accident participants are innocent, meaning that if conditions are bad you're best to stay off the road because of other bad drivers, not yourself...unless it's so bad everyone is home, in which case its safer :-) I also am very easy on my vehicles....they wear out slower. So I'm not inclined to do what you suggest, which BTW I agree is the prudent approach. I like the general truck, and engine, and Nissans, but right now I just want it running to unplug my shop. I wanted something smaller and simpler than my 68 GMC, but this 720 is not simpler. I want to sell the GMC; its simple but bigger than I want, and it has only a little more than half of the 720's miles. I also have a spare engine and trans for it. Maybe all it needs is power steering to make it more pleasant to drive. A Nissan answer is probably 2wd, and I have a 720 2wd diesel I haven't started working on yet. I have watched the oil pressure the little I've run this one and recall its12-15 at idle and 40-50 at say 3000. Head has 4 new int valves, touched up exhaust faces, new valve seals, same guides, and is straight. We'll see. Gotta fix it and run it first.
  12. OlDatZMan

    Boink boink

    Ok I just now posted what I thought was a big step fwd, but it wasn't, so I deleted it. That's good for you: it was long. The problem has advanced a lot since my last post but all that has happened isn't worth mentioning yet. What I thought was a valve/piston interference is not so, but the problem does seem to be that the missing half moon seal is jammed somewhere and not allowing the crank to move, or at least not with the force I'm willing to put on it. If the jam happens to be under a crank counterweight (or lowest part of the rotating crank assembly), as I just now realize it might be because the crank is stuck right at #1 BDC, then forcing the crank to rotate might not hurt anything. But if it is in a place where it could do some damage, like somewhere around the long distributor drive shaft, where forcing the crank to move might bend the shaft as the two gears try to mesh and suck the moon in, then I don't want to be forcing crank rotation. I'd really like to know exactly how much clearance distance there is between the crank at #1 BDC in the shallow front end of an 85 4x4 2.4 oil pan, or an oil screen or baffle if there is one there (Edit: especially clearance between the most forward counterweight and any stationary structure around its arc). I've never seen the inside of one of these pans. I have found a couple Google images. Will update when I know more.
  13. OlDatZMan

    Forum down today???

    I couldn't get on all Sunday, and it reminded me of all the extremely useful and interesting forums I have been on over the years which one fine day just disappeared forever. Tens of thousands of people actually relied on those forums to keep their lives moving by accessing information corporations either did not know, or if they knew did not want to give out. Part numbers and cross references would be just one. No matter what you'd like to think, the internet is not a reliable archive. Like any body of information you need backup in case a server implodes, some overworked forum volunteer misses a payment, a website name gets legally attacked, some critical person dies, one doesn't pay a bill, and on and on. The typical forum is very wordy, requires a lot of scrolling, is often filled with a lot of false leads before succinct info or a solution appears, takes up a lot of data space with useless or repeatedly quoted images and photos, and is time consuming if not hard to search. I've been on a forum with 20,000 entries, which is ok if you want to read 20,000 entries, but if you did, you'd find that half the people have no idea what they are talking about, and that even the ones that do know are "too busy" and will only read a page of two before the current page, and then ask questions or make comments that have already been answered or made numerous times. So a long thread, or a huge forum, is worse, not better. Stickies and archived condensations can concentrate useful info, and being relatively small can be archived by the site or even by forum members, but they are condensations and someone has to do the condensing. It is too much to expect forum admins to do that, they already are working overtime for members' benefit. Look 5 or 10 years ahead and you can guess the archive size of Ratsun. There's no good answer to this. The easiest answer is to ongoingly condense important info into separate documents, but that means one or more people per problem have to give the time to eliminate all the white space, jokes, personal attacks, wrong answers, and photo duplicates, and they have to know the subject to make those decisions. An organization that loses direct touch with its information for any reason is exactly like a person with Alzheimers. I have personal experience with Alz so I don't need any lippy rejoinders about it. Organizations and forums can get Alzheimers. If you rely on Ratsun to help you with your problems, you don't want that.
  14. OlDatZMan

    Wheel size for 73z without rubbing

    I had 16" Centerline oval hole mags with 225/50-16 Yoko 008's on them on my last 72Z. Those where the widest tires I could get at the time. I think they were 7" rims and I don't know the offset. I used wheel spacers, had clearance but not much to springs and to fender rims, but I later rolled up the inner fender lips about 45 degrees for more fender clearance. I probably had aftermarket springs on by then and they may have been a little shorter than OEM, but the clearance issues were to inside to springs and outside to fenders. I don't know anything about 17" wheels. I still have the Centerlines with the 008's still on them if anyone is interested.
  15. OlDatZMan

    Valve timing in degrees

    Wow, that's why Ratsun is terrific. Total elapsed time from question to answer: 10 minutes Thanks Mike.
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